I'm not sure what I'm looking for here but here is the output of the
inflight file immediately after the mdadm assemble hangs. Does this
indicate something accessing the array?
#cat /sys/block/md127/inflight
1 0
Also attached is an strace of my mdadm command that hung in case that
reveals something relevant:
strace mdadm --assemble --verbose
--backup-file=/root/mdadm5-6_backup_md127 --invalid-backup /dev/md127
/dev/sda /dev/sdh /dev/sdg /dev/sdc /dev/sde /dev/sdf --force 2>&1 |
tee mdadm_strace_output.txt
On Sun, May 7, 2023 at 7:23 PM Yu Kuai <yukuai1@xxxxxxxxxxxxxxx> wrote:
>
> Hi,
>
> 在 2023/05/06 21:19, David Gilmour 写道:
> >>From what I can tell it does look very similar. I stopped the
> > systemd-udevd service and renamed it to systemd-udevd.bak. My system
> > still hung on the assemble command. I'm not savvy enough to decode the
> > details here but does the "mddev_suspend.part.0+0xdf/0x150" line in
> > the process stack output suggest the same i/o block the other post
> > indicates?
> >
> > × systemd-udevd.service - Rule-based Manager for Device Events and Files
> > Loaded: loaded (/usr/lib/systemd/system/systemd-udevd.service; static)
> > Active: failed (Result: exit-code) since Sat 2023-05-06 06:59:11
> > MDT; 1min 27s ago
> > Duration: 1d 20h 16min 29.633s
> > TriggeredBy: × systemd-udevd-kernel.socket
> > × systemd-udevd-control.socket
> > Docs: man:systemd-udevd.service(8)
> > man:udev(7)
> > Process: 27440 ExecStart=/usr/lib/systemd/systemd-udevd
> > (code=exited, status=203/EXEC)
> > Main PID: 27440 (code=exited, status=203/EXEC)
> > CPU: 5ms
> >
> > ----------------------
> > #mdadm --assemble --verbose --backup-file=/root/mdadm5-6_backup_md127
> > --invalid-backup /dev/md127 /dev/sda /dev/sdh /dev/sdg /dev/sdc
> > /dev/sdb /dev/sdf --force
> > mdadm: looking for devices for /dev/md127
> > mdadm: /dev/sda is identified as a member of /dev/md127, slot 0.
> > mdadm: /dev/sdh is identified as a member of /dev/md127, slot 1.
> > mdadm: /dev/sdg is identified as a member of /dev/md127, slot 2.
> > mdadm: /dev/sdc is identified as a member of /dev/md127, slot 3.
> > mdadm: /dev/sdb is identified as a member of /dev/md127, slot 4.
> > mdadm: /dev/sdf is identified as a member of /dev/md127, slot 5.
> > mdadm: /dev/md127 has an active reshape - checking if critical section
> > needs to be restored
> > mdadm: No backup metadata on /root/mdadm5-6_backup_md127
> > mdadm: Failed to find backup of critical section
> > mdadm: continuing without restoring backup
> > mdadm: added /dev/sdh to /dev/md127 as 1
> > mdadm: added /dev/sdg to /dev/md127 as 2
> > mdadm: added /dev/sdc to /dev/md127 as 3
> > mdadm: added /dev/sdb to /dev/md127 as 4
> > mdadm: added /dev/sdf to /dev/md127 as 5 (possibly out of date)
> > mdadm: added /dev/sda to /dev/md127 as 0
> >
> > #hangs indefinitely at this point in the output
> >
> > ------------------------------------------
> >
> >
> > root 27454 0.0 0.0 3812 2656 pts/1 D+ 07:00 0:00
> > mdadm --assemble --verbose --backup-file=/root/mdadm5-6_backup_md127
> > --invalid-backup /dev/md127 /dev/sda /dev/sdh /dev/sdg /dev/sdc
> > /dev/sdb /dev/sdf --force
> > root 27457 0.0 0.0 0 0 ? S 07:00 0:00 [md127_raid6]
> >
> > #cat /proc/27454/stack
> > [<0>] mddev_suspend.part.0+0xdf/0x150
> > [<0>] suspend_lo_store+0xc5/0xf0
> > [<0>] md_attr_store+0x83/0xf0
> > [<0>] kernfs_fop_write_iter+0x124/0x1b0
> > [<0>] new_sync_write+0xff/0x190
> > [<0>] vfs_write+0x1ef/0x280
> > [<0>] ksys_write+0x5f/0xe0
> > [<0>] do_syscall_64+0x5c/0x90
> > [<0>] entry_SYSCALL_64_after_hwframe+0x63/0xcd
> >
> > #cat /proc/27457/stack
> > [<0>] md_thread+0x122/0x160
> > [<0>] kthread+0xe0/0x100
> > [<0>] ret_from_fork+0x22/0x30
> >
>
> Is there any thread stuck at raid5_make_request? something like below:
>
> Apr 23 19:17:22 atom kernel: task:systemd-udevd state:D stack: 0
> pid: 8121 ppid: 706 flags:0x00000006
> Apr 23 19:17:22 atom kernel: Call Trace:
> Apr 23 19:17:22 atom kernel: <TASK>
> Apr 23 19:17:22 atom kernel: __schedule+0x20a/0x550
> Apr 23 19:17:22 atom kernel: schedule+0x5a/0xc0
> Apr 23 19:17:22 atom kernel: schedule_timeout+0x11f/0x160
> Apr 23 19:17:22 atom kernel: ? make_stripe_request+0x284/0x490 [raid456]
> Apr 23 19:17:22 atom kernel: wait_woken+0x50/0x70
> Apr 23 19:17:22 atom kernel: raid5_make_request+0x2cb/0x3e0 [raid456]
> Apr 23 19:17:22 atom kernel: ? sched_show_numa+0xf0/0xf0
> Apr 23 19:17:22 atom kernel: md_handle_request+0x132/0x1e0
> Apr 23 19:17:22 atom kernel: ? do_mpage_readpage+0x282/0x6b0
> Apr 23 19:17:22 atom kernel: __submit_bio+0x86/0x130
> Apr 23 19:17:22 atom kernel: __submit_bio_noacct+0x81/0x1f0
> Apr 23 19:17:22 atom kernel: mpage_readahead+0x15c/0x1d0
> Apr 23 19:17:22 atom kernel: ? blkdev_write_begin+0x20/0x20
> Apr 23 19:17:22 atom kernel: read_pages+0x58/0x2f0
> Apr 23 19:17:22 atom kernel: page_cache_ra_unbounded+0x137/0x180
> Apr 23 19:17:22 atom kernel: force_page_cache_ra+0xc5/0xf0
> Apr 23 19:17:22 atom kernel: filemap_get_pages+0xe4/0x350
> Apr 23 19:17:22 atom kernel: filemap_read+0xbe/0x3c0
> Apr 23 19:17:22 atom kernel: ? make_kgid+0x13/0x20
> Apr 23 19:17:22 atom kernel: ? deactivate_locked_super+0x90/0xa0
> Apr 23 19:17:22 atom kernel: blkdev_read_iter+0xaf/0x170
> Apr 23 19:17:22 atom kernel: new_sync_read+0xf9/0x180
> Apr 23 19:17:22 atom kernel: vfs_read+0x13c/0x190
> Apr 23 19:17:22 atom kernel: ksys_read+0x5f/0xe0
> Apr 23 19:17:22 atom kernel: do_syscall_64+0x59/0x90
>
> By the way, cat /sys/block/mdxx/inflight can prove this as well.
>
> If this is the case, can you find out who is accessing the array?
>
> Thanks,
> Kuai
>
<<attachment: mdadm_strace_output.zip>>
